Work-supporting arm for sewing machines



July 29. 1924.

' J. BERGER WORK SUPPORTING ARM FOR SEWING MACHINES 2 Sheets-Sheet. 1

Filed May 23, 1921 J i -Tg J. BERGER WORK SUPPORTING ARM FOR SEWING MACHINES Filed May 25. 192) 2 Sheets-Sheet 2 Patented July 29, 1924.

JOSEPH BERGER, OF UTICA, NEW YORK, ASSIGNOR TO UNION SPECIAL MACHIKE GOM- I PANY, OF CHICAGO, ILLINOIS, A CORPORATION O'F ILLINOIS.

WORK-SUPPORTING ARM FOR S EVVING MACHINES.

Application filed May 23, 1921. Serial No. 471,750.

To all whom it may concern: I

Be it known that I JOSEPH BERGER, a citizen of the United States, residing at Utica, in the county of Oneida, State of New York,

have invented certain new and useful Improvements in'Work-Supporting Arms for Sewing Machines, of which the following is a description, reference'being had to the accompanying drawing and to the figures of reference marked thereon.

The invention relates to new and useful improvements in work supporting arms for sewing-machines, and more particularly to a sewing machine wherein a threaded looper is located in the work supporting arm and cooperates with one or more needles in the stitching of the fabric.

An object of the invention is to provide a work supporting arm wherein the portion of the arm in the region of the looper is formed in sections, one of which is hinged so as to swing to uncover the looper to fa" cilitatethe threading of the same.

Another object of the invention is to provide a work supporting arm of the above type wherein said swinging section of the work supporting arm is located beneath and at one side of the throat plate so as to give better access to the looper for the placing and the removing of the same as well as threading. V

Still another object of the invention is to provide a work supporting arm of the above type whereinthe swinging section of the arm is mounted so as to swing about an axis parallel with the longitudinal axis of the work supporting arm.

These and other objects will in part be obvious andwill in part be hereinafter more fully disclosed.

In the drawings, which show by way of illustration one embodiment of the invention: d Figure 1 is a top plan view of the forward end of a work supporting arm embodying my improvements;

Fig. 2 is a sectional view on the line 2-2 of Fig. 1;

\ Fig. 3 is a side view of the arm shown in Fig. 1 with a movable section of tl 1e work supporting arm thrown to open positlon, and in dotted lines indicating the position of the needles and'looper,

Fig. 4 is a sectional view on the line 4-4 of Fig. 1, the looper mechanism and feeding mechanism being omitted;

Fig. 5 is a perspective View of the movable section of the arm and the fixed section adjacent the movable section and which supports the same. M

The invention consists broadly in a work supporting arm which is particularly adapted for stitching tubular articles, said arm being provided with the usual feed slots through which the fabric engaging sections of the feed dog work, and located in the free end of the arm is a threaded looper. My work supporting arm is particularly adapted for a machine having a plurality of needles-and wherein the loopercooperates with all the needles. The looper moves in a plane at right angles to the longitudinal axis of the work supporting arm when entering and leaving the loops of the needle threads or substantially so. The feed slots are formed in a throat plate which contains th needle openings and is of the usual con struction.

Beneath a portion of the throat plate, the supporting arm is formed in two sections,

one of which is fixed to the arm and the other of which is mounted so as to swing for uncovering the looper so as to give access thereto for changing the looper or for threading th looper. The swinging section preferably moves about an axis parallel with the longitudinal axis of the work support. Said swinging section extends from a point substantially atone side of the throat plate to a point substantially diametrically opposite thereto so that, when said swingingsection is moved, the looper is uncovered both beneath andat the side of the arm.

Referring more in detail to the drawings,

my work supporting arm consists of a por tion 1 which is substantially cylindrical and fixed to said portion is a throat plate 2 provided with feed slots 33 and a needle opening 4 in which projects stitch fingers 5-5. This throat plate is secured to the end of the arms by means of screws 6 -6 and projects beyond the main section 1, as I clearly shown in Figs. 1 and 3 of the drawings. The work supporting arm is provided with the usual feeding mechanism which includes a feed dog having fabric'engaging portions 7--7 which work in the feed slots 33. I

Extending lengthwise of the arm is a suitable shaft in which is mounted a looper carrier 8. Mounted on said looper carrier 8v is a looper 9 which is provided with an eye 10, a thread groove 11, and an eye at the heel of the looper, which ar of the usual construction. In other words, the looper is a thread carrying looper. In the present embodiment of the invention, I have shown the machine as having three needles 12 .12 l2 carried by a needle bar 13. The looper 9 cooperates with all three needles.

Beneath the projecting portion of the throat plate and forming a part of the work supportingarm are two sections 14 and 15.

p The section 14: is provided with .an inwardsubstantially diametrically ly projecting flange 15 which is slotted 16 to receive abolt 17 by which the section 141 is secured to the end of the main section 1 of the work supporting arm. Said section 14 is also provided with a laterally projecting flange 1 7 which forms a part of the end of the work-supporting arm. Said section 14 is also provided with a project ing lug 18 which has an. opening 19 extending. therethrough.

The section 15 is a swinging section, and said section has spaced perforated lugs 20 and 21 which are disposed at the ends of 'the lug 18 and are provided with openings 22+.22 so that; a pivot bolt 23 may extend through the openings. Said pivot bolt, as indicated in dotted lines in Fig.

3, is carried by the main section 1 of the work supporting arm and extends in a direction parallel with the longitudinal axis of the arm. The two sections 14 and 15 are assembled so as to aline the openings 19 and 22.; they are then placed on the pivotbolt 23, and the'bolt or screw 17 inserted. for securing the section 14 rigidly to the end of the main section of the arm. A set screw or locking pin 24 serves to hold the pivot pin 23 in place in the main section of the arm. The section; 15 is provided with a projecting flange 25 which together with the flange 17 a close the end of the work supporting arm. Said section is also provided with parallel ribs 26 which serve as a thumb hold for swinging the section The section 15 is curved in cross section and extends from a point just below the throat plate at one side thereof to a point opposite. In other words, the extent of the curved surface of the section 15 in cross section is about 180. When the section is moved from the full line position shownin Fig. 2 to the dotted line position, it will be apparent that the looper is exposed not only on one side of the arm but for a portion ofthe arm beneath the looper, and this gives free access for the threading of the looper at the heel as well as at the point and for the removing and replacing of the looper when desired. When the swinging section 15 is moved so as to cover the looper, it is held in this position by means of a spring clip 27 which is secured byrmeans of screws 28 to the flange 15 and is adapted to engage over a rib and lug 29. This clip is bent near its free end to form a shoulder which snaps behind the lug 29 and thus the swinging section is held in closed position. The operator, by exerting a slight pressure on the ribs 26 in a direction away from the lug 29 may quickly disconnect the spring clip from the lug and turn the movable section to the dotted line position shown in Fig. 2, or the full line position shown in Fig. 3. Th thread for the looper passes along a groove 30 in the work supporting arm, which groove is closed by a cover plate 31. The thread is then led through an opening and is guided by a guide wire 33 as it passes to the heel of the looper.

It is obvious that minor changes in the details of construction may be made without departing from the spirit of the in vention as set forth in the appended claims.

Having thus described the invention, what I claim as new and desire to secure by Letters-Patent is 1. The combination of a work supporting arm having a throat plate and shaft extending longitudinally of said arm and disposed centrally therein, a thread carrying looper mounted on said shaft, said arm beneath a portion of the said throat plate being formed in two sections, one of which is rigid with the arm and the other of which is mounted to swing about an axis parallel with the longitudinal axis of the arm, said movable section extending from a point at one side of the throat plate to a point substantially diametrically opposite thereto, whereby when said movable section is swung downwardly the looper at both the heel and the point will be exposed to facilitate the threading thereof.

2. The combination of a work supporting arm having a throat plate and shaft extending longitudinally of said arm and disposed centrally therein, a thread carrying looper mounted on said shaft, said arm beneath a portion of the said throat plate being formed in two sections, one of which is rigid with the arm and the other of which is mounted to swing about an axis parallel with the longitudinal axis of the arm, said movable section extending from a point at one side of the throat plate to a point substantially diametrically opposite thereto, whereby when said movable section is swung downwardly the looper at both the heel and the point will be exposed to facilitate the threading thereof, said stationary section having an end flange and said swinging section having an end flange, said end flanges together operating to close the end of the work support.

3. The combination of a work supporting arm having a throat plate, a thread carrying looper mounted beneath the throat plate, said arm beneath a portion of said throat plate being formed in two sections, one of which is rigid with the arm and the other of which is mounted to swing about an axis parallel with the longitudinal axis of the arm, said movable section extending from a point at one side of the throat plate to a point substantially diametrically opposite thereto, one of said sections having a spring clip and the other section having a lug adapted to be engaged by said clip to hold the swinging section in closed position.

4:. The combination of a work supporting arm having a throat plate, a thread carrying looper mounted beneath the throat plate, said arm beneath a portion of the throat plate being formed in two sections, one of said sections being rigidly secured to the main portion of the arm and the other of said sections being mounted to swing about an axis parallel with the longitudinal axis of the arm, said movable section extending from a point at one side of the throat plate to a point substantially diametrically opposite thereto, said fixed section having spaced lugs with openings therethrough, said movable section having a projecting lug with an opening therethrou'gh located in alinement with the spaced lugs in the fixed section, .a pivot pin extending through the lugs on the fixed sec tion and the movable section and secured to the main portion of the arm for aiding in supporting the fixed section and the movable section from the main portion of the arm.

5. The combination of a work supporting arm having a throat plate, a thread carrying looper mounted beneath the throat plate and movable from right to left as viewed by the operator when entering the needle thread loops, said arm beneath a portion of the throat plate being formed in two sections, one of which is rigid with the arm and the other of which is mounted to swing about an axis parallel with the longitudinal JOSEPH BERGER. 

